my pond is in full sun all day every day. other than warmer than usual water temps i havent seen any detriment to the pond...no green water, no string alge to speak of, crystal clear water. plants all doing well. fish have remained active altho slightly less than the norm. but we are getting a reprieve from the heat today and the next few days. weve gotten some decent rain over the last day or 2 and the grass is geen not "crunchy" as addy says any more...its been golden brown for 2 weeks. they imposed watering restrictions here ... and even then the hours are 11:00 pm til 5:00 am which is fine if youve got a sprinkler system..but we dont.